Ring of Frost (3.5e Equipment)
From D&D Wiki
Ring of Frost: This silver ring set with a small blue stone is always cool to the touch. Pointing the ring at a target and whispering a command word will allow project a Ray of Frost (caster level 1st) from the stone. While this normally does only minor damage, in the hands of rogues or assassins who know the right spot to attack on an unwary opponent, it can be deadly.
Faint Evocation;CL 1; Forge Ring, ray of frost; Market Price: 901 gp